Clips or fasteners are known for removably mounting a first structure to a second structure provided with a mounting opening. The first structure can have an insertion rib with an insertion slot, and the clip or fastener is configured to be attached to the insertion rib by way of the insertion. The clip or fastener is also configured to be received in the mounting opening. Typically, the first structure might be a trim piece and the second structure might be an instrument panel or other vehicular sub-structure. Several clips can be used to mount the first structure to the second structure.